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Fiber Class Questions and Answers
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Light is electromagnetic energy with a ____________ frequency and a ___________ wavelength compared to radio waves. ✔✔Higher/Shorter
Fiber optic transmission takes place in the ___________ portion of the light spectrum. ✔✔Infrared
A simple fiber optic system would consist of what 4 parts? ✔✔Transmitter/Fiber optic Cable/Receiver/Connector
What absolute power value is zero dBm referenced to? ✔✔1 miliwatt
Absolute power in optical fiber is specified as: ✔✔dBm
Attenuation in optical fiber is lowest at what wavelength _________ ✔✔ 1550
What are the three most common wavelength windows used for communications through optical fibers? ✔✔850/1300/
In North America what year was the first fiber optic telephone system installed? ✔✔ 1977
Single-mode fiber optic systems typically use what light source? ✔✔Laser Diode
Multi-mode fiber optic transmitters typically use what two low cost light sources? ✔✔LED / VCSEL
Different wavelengths of light travel at ___________ speeds through the glass. ✔✔different
Single-mode fibers have a _______________ core compared to multi-mode fibers. ✔✔smaller
The typical numerical aperture (NA) for a 50/125 um optical fiber is? ✔✔. 200
One way to reduce modal dispersion is to? ✔✔use a smaller core(single mode)
Improper bending of an optical fiber will do what to the tensile strength? ✔✔decrease
OM3 and OM4 multi-mode fibers are commonly known as_____________ fibers. ✔✔laser optimized multi-mode
What are the two most common multi-mode optical fiber types? ✔✔62.5/125um and 50/125um
The typical coating diameter for a fiber used in tight-buffered cables is? ✔✔900um
In cordage what color signifies single-mode fiber? ✔✔yellow
In ANSI/TIA-598-C twelve colors comprise the fiber color code. What are the twelve in order? ✔✔1.Blue 2. Orange 3. Green 4. Brown 5. Slate 6. White 7. Red 8. Black 9. Yellow 10. Violet
- Rose 12. Aqua
This fiber is designated by the ISO/IEC 11801 specification. The fibers designated as OM1 and OM2 are generally known as ________________ fibers and were designed for use with LED light sources. ✔✔Legacy Multi-mode
Graded index fiber uses numerous concentric layers of glass to reduce____________ dispersion. ✔✔modal
Which component of the connector is the optical fibers cladding typically bonded to during the assembly process? ✔✔ferrule
The NEC defines a fiber optic cable that is fire retardant and low smoke as a ________________ rated cable. ✔✔plenum
What color is a single mode connectors strain relief, adapter housing, and plug body? ✔✔Blue
The gel/tape/powder in a loose tube/buffered fiber cable protects the optical fiber from_______________ should the sheath or jacket fail. ✔✔water
What does "OFNR" mean? ✔✔Optical Fiber Nonconductive Riser
An SC connector is a recognized connector in the ANSI/TIA-568-C.3 standard? True or False ✔✔True
What safety forms must be available when chemicals are used? ✔✔Material Safety Data Sheet (MSDS)
What is the best way to dispose of waste fiber ends? ✔✔Fiber optic disposal unit
The loss resulting from mated fiber ends that are not perpendicular to the fiber's axis and are not lined up with one another due to a poor cleave angle in an example of _________________ loss. ✔✔extrinsic
Most small form factor connectors use this diameter ferrule. ✔✔1.25mm
The NEC is updated every __________________ years? ✔✔three
If the cable has metallic members, what does the NEC require at termination points? ✔✔bonding and grounding
What kind of cable kit branches the fibers contained in a loose tube fiber optic cable into 900 micron outside diameter protective tubes? ✔✔Fan out kits
Most single-mode fiber ends are terminated onto factory made________________ and spliced to the fiber cable. ✔✔pig-tails
What type of loss can be greatly reduced by using an optically transparent index-matching gel having a refractive index the same as or very near that of the optical fibers? ✔✔Fresnel Reflection
This termination technique depends on the quality of the cleaving tool for optimum performance. ✔✔No polish connector
When installing cable. it is recommended that ______________ be available for future changes and restorations. ✔✔slack
What is not required with cable management products? ✔✔Specifying fiber type
When visually inspecting the end face of a connector with an inspection microscope, where are the minor defects allowed? ✔✔Outer cladding
If you have a cross section of a fiber optic cable where is the cladding (center circle, middle, or outer ring)? ✔✔middle
What is the acronym for LASER? ✔✔Light Amplification by Stimulated Emissions of Radiation
What does "OFCR" mean? ✔✔Optical Fiber Conductive Riser
What are the 3 methods of fiber fabrication to making a preform? ✔✔1. MCVD (modified Chemical Vapor Deposition) 2. OVD (Outside Vapor Deposition 3. VAD (Vapor Axial Deposition)
What is the diameter for the acrylate coating? ✔✔250um
There are three types of dispersion. What are they? ✔✔modal, chromatic (material), waveguide
A connector that is not fully seated would result in an air gap. What would this air gap cause? ✔✔Fresnel Reflection
What type of multi-mode optical fiber would be contained in and aqua jacket? ✔✔50/125 um laser optimized
Which class of lasers has the highest power and is used for surgery, research, drilling, cutting, welding and micro-machining? ✔✔Class 4
Angled Physical Contact(APC) connectors offer a significant reduction in _______________? ✔✔Reflectants
What does ETA stand for? ✔✔Electronics Technicians Association
Name 3 ways fiber optics is used today? ✔✔1. Medical 2. CCTV 3. Communications 4. Military
- Car Audio 6. Utilities 7. Security Systems
Fiber optics transmissions are viewable to the naked eye. True or False? ✔✔False
What is the last event on an OTDR trace? ✔✔Noise floor
What is the initial test run on a Fusion Splicer when first turning on the equipment? ✔✔Arc test
The optical fiber cabling components standard (ANSI/TIA-568-C.3) used for commercial buildings specifies the maximum insertion loss for a mated connector pair as? ✔✔.75dB
What test equipment requires periodic and traceable calibrations? ✔✔Optical power meter
The splicing environment must be kept as __________________ as possible. ✔✔Clean
The Telcordia general recommendation GR-326 CORE specification recommends that fiber optic connectors have a repeatability value of not greater than___________________? ✔✔.2dB
A panel used to provide a central location for cross connecting, monitoring or testing fiber is a? ✔✔Patch panel
This product is mostly used in outside plant applications for splicing and routing of optical cables. ✔✔Closure
What type of test equipment typically uses a red laser light? ✔✔Visual Fault and Locator (VFL)
What instrument is used for testing of fiber spans and includes loss per kilometer and total distance of span measurements? ✔✔Optical Time Domain Reflectometer (OTDR)
Installers must consider what when installing fiber optic cables? ✔✔Building Codes
A cables sequential marking is useful in determining the approximate _______________ of the cables. ✔✔Length
According to the NEC, what is the maximum fill ratio percentage by cross sectional area for conduit with one cable? ✔✔ 53
According to Telcordia GR-20 and GR-765, what is the maximum FUSION splice loss allowable? ✔✔- .1dB
